Muscle Diseases Flashcards
how do muscles diseases typically present?
myalgia
muscle weakness
stiffness
abnormal bloods
name the 2 inflammatory myopathies
polymyositis
dermatomyositis
most common age to be affected by an inflammatory myopathy
40-50 years
features of inflammatory myopathies on muscle biopsy
muscle fibre necrosis
degeneration
regeneration
inflammatory cell infiltrate
is muscle weakness usually symmetrical or asymmetrical?
symmetrical
what is gottrons sign
symmetric, occasionally scaling, violaceous erythematous eruption over the extensor surfaces of the metacarpophalangeal and interphalangeal joints of the fingers
which muscle disease is associated with a heliotype rash?
dermatomyositis
GI effects of dermatomyositis
dysphagia
CV effects of dermatomyositis
myocarditis
lung effects of dermatomyositis
ILD
which muscle disease is most likely to get malignancy?
dermatomyositis
most common malignancies to arise in muscle disease
ovarian breast stomach lung bladder colon
presenting symptoms of dermatomyositis
tired muscles functional difficulty raynauds weight loss cough breathlessness muscle pain
what is confrontational testing?
direct testing of power eg pushing arm down while they resist
what is isotonic testing
30 sec sit to stand test
blood tests used in polymyositis?
CK
inflammatory markers
electrolytes, calcium, PTH, TSH
ANA, Anti-Jo-1
what is CK
a muscle enzyme
what is electromyography
increasing fibrillations, abnormal motor potentials, complex repetitive discharges
diagnostic techniques for myositis
muscle biopsy
MRI
EMG
treatment for myositis
glucocorticoids
azathioprine
methotrexate
most common misdiagnosis for inclusion body myositis
polymyositis
presenting feature of inclusion body myositis
distal muscle weakness
why is inclusion body myositis called this?
inclusion bodies on biopsy
are CK levels higher in inclusion body myositis or polymyositis
polymyositis
age group affected by polymyalgia rheumatica?
over 50s
which areas of the world most commonly get it
northern countries
what disease is polymyalgia rheumatica commonly associated with?.
temporal arteritis/giant cell arteritis
clinical presentation of polymyalgia rheumatica
morning stiffness that improves throughout the day
ache in shoulder/hip
symmetrical
“cant get out of bed”
clinical presentation of the arteritis that follows polymyalgia rheumatica
headache
scalp tenderness
jaw claudication
visual loss (if optic artery damaged)
does inclusion body myositis affect the distal muscles?
yes
does polymyositis affect the distal muscles
no, affects proximal
which inflammatory markers are raised in polymyalgia rheumatica
raised ESR, plasma viscosity, CRP
treatment of PMR?
very good reaction to low dose steroids
if arteritis, higher dose
who commonly gets fibromyalgia
women of child bearing age
what causes fibromyalgia
depression
stress
clinical presentation of fibromyalgia
muscle stiffness pain muscle tension fatigue trouble sleeping chest pain headache cognitive difficulty worse on exertion
what pathogenic processes occur in fibromyalgia
hypersensitivity to pain
associated conditions to fibromyalgia
depression
IBS
treatment for myalgia
antidepressants
strong analgesics eg gabapentin, pregabalin, mild opiates
physio/OT/cognitive behavioural therapy
elderly man with heavy feeling in arms struggling to climb stairs with a high CK
polymyositis
